Throttling valve



Aug. 2, 1932'. A. L. TOBIN 1,869,832

TTTTTTTTTTTTTT E Patented Aug. 2, r 1932 P TENT. OFF E-.4

Anr'inn LITTLE 'IOBIN, or SALEM, MASSAoHUSEr'rS, SSIGNoR r RUGG ES-l KmnenMANN MFG. co, or SALEM, MASSACHUSETTS 'THROTTLING- VALVE Application filed November 12, 1927. Serial No. 232,797.

the main valve back into a. regulating position, leaving the bypass open until such time as the main valve is near its closed position and then automatically closing the bypass and again driving the main valve back intoa regulating position.

t will be understood that when fan engine throttling valves are connected to regulators of the servo motor. or other type commonly used to control boiler operation, that the throttling valve must be of a size which will supply t. e necessary amount of steam a a M: 1 M a If 1 ioi any possible pea; luad condition. I no valve is of a suiiicient size to supply the nec essary steam to the fan engine to mainta n say 200% boiler ratlng then it wlll be too large when boilers are operated at normal rating of say 100%. Where the valve is too large for the requirements, the regulator becomes an off and on affair, resulting in the fan engine being slowed down to idling speed half of the time, and the other half, producing a speed of the fan much too great for the requirements. smaller valve, but with the smaller valve no means is provided for automatically taking care of the peak load condition. -My invention meets the requirements of a satisfactory throttling valve for normal condition and one which will automatically adjust itself to take care of an extreme condition. I

Referring to the drawing Fig. 1 shows a vertical section through the valve casing showing the arrangement of main and bypass valves. tieal elevation of he valve and the arrangement of its operating levers.

Referring to Fig. l, (1) represents thevalve casing; (2) the main valve; the bypass valve; (4) is the port through the main,

The remedy is in using a Fig. 2 shows an exterior ver valve; and (5) is the port through the by pass valve. i A

Referring to Fig. 2, (6) is the operating lever which controls the operation of main valve (2) and is the by-pass valve arm. It will be understood that both the main and by-pas's valves have stems which extend through 'stufiing boxes and" connect to the outside operating member (6) and in" such a manner as tobe' operated thereby. crank pin (8.) is secured to the end of arm (7.) and has a roll (9) which enters a slot' (10)inthe lever (6). As shown in thedraw- 7 ing the valveis in a closed-position, both ports (4) and (5) being closed. If the lever (6) shouldbe moved to the left it will rotate and open the main'valve so steam will pass fromeither end of the valve, which ever is used as the inlet, to thejoutlet of the valve. Itwill be seen that the opening the main valve will not disturb the'pos1tionofthe arm (7),*theby-pass valve- (3') remaining closed until the main valve '(2') is" opened to av pointwheretheopposite end of the slot (10) 'engagesthei roll (9) and then both valves will be rotated and moved totheir open position. v i o Should the main valve then be'moved to- Ward its closed position the by-pass'valve will remain open until the main valve has reached tonearly its closed position when the'roll ('9) will-be again engaged and both valves moved toa closed positionasshown in the drawing; It will be seen that the by-pass valve has a shorter operating arm than the main valve and therefore, a'mueh quicker motion. The: travel of the by-pass is also much'lessbetween open and closed, positions than that of the main valve. This means that themain valve I can be 7 operated to approximately threefourths closed before starting to close the bypass, and likewise operated tothree-fourths open before starting to open the by-pass, both valves completing their final opening or' clos '1 ing movement simultaneously. 1

I claim: p o i V 1. In a throttling valve comprising a valve casing havingan inlet andan outlet for the 7 passage of pressure fluid, a main valve-and a 'by-pass I valve in said casing, an actuating member for operating the main valve and means whereby said actuating member operates the by-pass valve at near the open and closed positions of the main valve only to thereby further increase and decrease the flow of pressure fluid through said casing.

2. In a throttling valve comprising a. valve casing, a main valve and a bypass valve in said casing, an actuating member for operating the main valve uniformly between its open and closed positions, and means whereby said actuating member operates the bypass valve intermittently at near the open and closed positions of the main valve only to thereby further increase and decrease the flow of pressure fluid through said casing.

3. In a throttling valve comprising a valve casing, a main valve and a by-pass valve in said-casing, an actuating member for operatingthe main valve, said actuating member also operating the by-pass valve, but with a lost motion to allow the by-pass to remain closeduntil the main valve is nearly open, and likewise, to allow the by-pass to remain open untilthe main valve is nearly closed the arrangement being such as to further in.-

crease and: decrease the'capacity of said valve.

i t. In a throttlingvalve comprisinga valve casing having an inlet and: an outlet for the passage ofpressure fluid, a main; valve and a by-pass valve in said casing both valves being-arranged to retard the flow ofpressure ofi'steamtfrom' the-inlet to the outlet, a bypass valve: located: in a'passage extending around the I'nain valve fromv the inlet to the outlet, theearrangement being such that the main valve operating; means, also controls the operation oifthe-by-pass valve near the open and closedwpositionsof the main-valve only, to thereby-further increase and decrease the flow of; steam through-said valve casing.

6; In a steam, throttle valve, the combination ot a valve casingh'a-vin g an inlet and an outlet, a: main valve insaid casing, means to operate themain val-veto control the flow of steamz firomthe inlet to the outlet, a; by-pass valve located in a passage extending around the main valve from the inlet to the outlet ope-ratingmeansfor said by-pass valve, a lost IIIOt IOH connection between the operating means; 055 the main valve and the operating meansof the by-pass valve, the arrangement ARTHUR LITTLE TOBIN. 

